BGS 80, Anthocyanin-less 2, ant2

Purple straw = P or Pr (12, 15).
Anthocyanin-less = ant-2 (3, 10).
Exrubrum = rub (6).
Colorless leaf tip 2 = clt2 (7), c2 (7).
Basic helix-loop-helix domain / Myelocytomatosis (bHLH / MYC) = HvbHLH1 (13).

Monofactorial recessive (3, 12).
Located in chromosome 2HL (3, 12), Ant2.c (Pr) is about 15.1 cM distal from the vrs1 (six-rowed spike 1) locus (5, 8, 12, 14, 16); Ant2 (Pr) locus is about 5.5 cM from the Pre2 (Purple lemma and pericarp 2) locus (8); ant2.20 has no SNP markers in the Bowman backcross-derived line, BW019, that are deviant from those of Bowman (2); ant2.h is associated with SNP markers 1_0247 to 2_0182 (positions 150.96 to 185.53 cM) in 2H bins 10 to 12 in Bowman backcross-derived line BW020 (2); ant2 from Saffron cosegregated with SNP markers 2_1007 and 2_1175 [position 98.82 cM (155.04 to 155.98 cM)] in 2H bin 10 (1). Ant2.c is between markers bmag140 and bmag125 in 2HL (13).

As plants approach maturity straw remains colorless instead of turning purple (10, 12). As plants approach maturity, anthocyanin pigments are not observed in any vegetative plant parts, including the stem, auricles, lemma, and awns (3, 7, 10). The recommended symbol for the dominant allele is Ant2.c (formerly Pr) (10). Besides the lack of anthocyanin pigmentation of the stem bases, no other morphological differences were observed between Bowman and the Bowman backcross-derived lines for ant2.20 (BW019) and ant2.h (BW020) (4). Resequencing the putative anthocyanin pathway gene ant2 (HvbHLH1) identified a 16-bp deletion resulting in a premature stop codon upstream of the basic helix-loop-helix domain (1). The Pre2 and Ant2 loci were assumed as non-synonymous because the purple- and white-grained cultivars used for mapping Pre2 did not have polymorphism for the Ant2 diagnostic marker (11).

Natural occurrence in few cultivars (9, 12), the first 3 or 4 alleles are likely natural occurrences the same locus.

Ant2.c (Pr) in Nilsson-Ehle No. 2 is the wild type allele and colorless straw in Trebi (CIho 936) (12); ant2.d (pr1.b) in Alva (NGB 1507, NSGC1866), ant2.e (pr1.c) in Balder (NGB 14668, PI 195481), ant2.f (pr1.d) in Cambrinus (PI 321779), ant2.g (pr1.e) in Sultan (PI 339814) (9); ant2.h in Shyri from ICARDA in Mexico (2); ant2.15 (NGB 114564), 2.20 (NGB 114569, GSHO 1632), 2.23 (NGB 114572), 2.25 (NGB 114575), 2.26 (NGB 114576), 2.27 (NGB 114278) in Foma (NGB 14659, CIho 11333) (10); ant2.41 (NGB 114596) in Mari (NGB 14656, PI 428407) (9); ant2.46 (NGB 111505) in Foma, 2.47 (NGB 111823), 2.48 (NGB 111782), 2.49 (NGB 111808), 2.50 (NGB 111811), 2.51 (NGB 111817), 2.54 (NGB 111872), 2.55 (NGB 111787) in Bonus (NGB 14657, PI 189763) (9); 2.112, 2.113, 2.114, 2.115, 2.116, 2.117, 2.118, 2.120, 2.121, 2.122, 2.130 in Nordal (NGB 13680, NGB 4704) (9); ant2.h (pr1.f) in Shyri (GSHO 2430) (4).

Ant2.c (Pr) in Trebi (CIho936), ant2.20 (NGB 114569, GSHO 1632) in Foma; ant2.h (GSHO 2430) in Shyri; ant2.h from Shyri in Bowman (PI 483237, NGB 22812)*5 (GSHO 1919); ant2.h in Bowman*7 (BW020, NGB 20428); ant2.20 (NGB 114569, GSHO 1632) from Foma in Bowman*2 (GSHO 1920); ant2.20 in Bowman*6 (BW019, NGB 20427).

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2. Druka, A., J. Franckowiak, U. Lundqvist, N. Bonar, J. Alexander, K. Houston, S. Radovic, F. Shahinnia, V. Vendramin, M. Morgante, N. Stein, and R. Waugh. 2011. Genetic dissection of barley morphology and development. Plant Physiol. 155:617-627.
3. Finch, R.A., and E. Simpson. 1978. New colours and complementary colour genes in barley. Z. Pflanzenzücht. 81:40-53.
4. Franckowiak, J.D. (Unpublished).
5. Gill, T.S. 1951. Inheritance of 16 barley characters and their linkage relationships. M.S. Thesis. Utah State Univ., Logan.
6. Gustafsson, Å., A. Hagberg, U. Lundqvist, and G. Persson. 1969. A proposed system of symbols for the collection of barley mutants at Svalöv. Hereditas 62:409-414.
7. Hayashi, J., R. Takahashi, and I. Moriya. 1977. A linkage study of two complementary genes conditioning anthocyanin pigmentation in barley plants. Nogaku Kenkyu 56:167-178.
8. Heiner, R.E. 1958. Linkage and inheritance studies in barley. M.S. Thesis. Utah State Univ., Logan.
9. Jende-Strid, B., and U. Lundqvist. 1978. Diallelic tests of anthocyanin-deficient mutants. Barley Genet. Newsl. 8:57-59.
10. Jende-Strid, B. 1984. Coordinator's report: Anthocyanin genes. Barley Genet. Newsl. 14:76-79.
11. Jia, Q., J. Zhu, J. Wang, J. Yang, and G. Zhang. 2015. Genetic mapping and molecular marker development for the gene Pre2 controlling purple grains in barley. Euphytica 208:215-223.
12. Robertson, D.W. 1933. Inheritance in barley. Genetics 18:148-158.
13. Shoeva, O.Y., H.-P. Mock, T.V. Kukoeva, A. Börner, and E.K. Khlestkina. 2016. Regulation of the flavonoid biosynthesis pathway genes in purple and black grains of Hordeum vulgare. PloS ONE 11(10): e0163e782.
14 Takahashi, R., J. Hayashi, and I. Moriya. 1971. Linkage studies in barley. Barley Genet. Newsl. 1:51-58.
15. Waddoups, H.M. 1949. A study of semisterility and its linkage relationships in translocation stocks of barley. M.S. Thesis. Utah State Agr. Coll. 66 pp.
16. Woodward, R.W. 1957. Linkages in barley. Agron. J. 49:28-32.

T.E. Haus. 1975. Barley Genet. Newsl. 5:107 as BGS 53, Purple straw, Pr.

J.D. Franckowiak and U. Lundqvist. 1997. Barley Genet. Newsl. 26:118.
J.D. Franckowiak and U. Lundqvist. 2015. Barley Genet. Newsl. 45:98-99.
J.D. Franckowiak and U. Lundqvist. 2016. Barley Genet. Newsl. 46:55-56.
J.D. Franckowiak and U. Lundqvist. 2016. Barley Genet. Newsl. 48:80-81.